WPF - 設置WebBrowser無法正常工作的代碼可見性

Question

我有兩個元素，WebBrowser和Slider，我試圖隱藏一個並顯示另一個，具體取決於用戶打開的文檔類型，PDF或視頻文件（mp4）。 但是，目前，當我打開PDF文件時，WebBrowser仍然是隱藏的。

在MainWindow.xaml中，我有

<WebBrowser x:Name="PDFView" Width="600" 
                    Height="410" Visibility="{Binding PDFVisible}">
</WebBrowser>

<FFmpegFramework:MediaElement Grid.Row="0" x:Name="MediaElement"
                    Height="400" Background="Gray"  Visibility="{Binding VideoVisible}"/>

在MainWindow.xaml.cs中，我有

else if (fileName.Contains("pdf"))
{

    MainWindowViewModel dataContext = this.DataContext as MainWindowViewModel;
    dataContext.PDFVisible = Visibility.Visible;
    dataContext.VideoVisible = Visibility.Collapsed;

    //PDFView.Navigate("file:///" + fileName);
}
else if (fileName.Contains("mp4"))
{
    MainWindowViewModel dataContext = this.DataContext as MainWindowViewModel;
    dataContext.PDFVisible = Visibility.Collapsed;
    dataContext.VideoVisible = Visibility.Visible;
}

在MainWindowModel.cs中，我有：

public Visibility PDFVisible
{
    get
    {
        return fPDFVisible;
    }
    set
    {
        this.SetProperty<Visibility>(ref fPDFVisible, value);
    }
}

public Visibility VideoVisible
{
    get
    {
        return fVideoVisible;
    }
    set
    {
        this.SetProperty<Visibility>(ref fVideoVisible, value);
    }
}

private Visibility fPDFVisible = Visibility.Collapsed;
private Visibility fVideoVisible = Visibility.Visible;

Answer 1

您在.xaml.cs文件中進行此更改，而不是為什么要創建objects來更改visibility 。 您可以通過控件名稱直接更改visibility

if (fileName.Contains("pdf"))
{
    PDFView.Visibility = Visibility.Visible;
    MediaElement.Visibility = Visibility.Collapsed;
}
else if (fileName.Contains("mp4"))
{
    PDFView.Visibility = Visibility.Collapsed;
    MediaElement.Visibility = Visibility.Visible;
}

並且不要忘記在綁定中更改“Mode = TwoWay”。 它還將在ViewModel更改屬性

<WebBrowser x:Name="PDFView" Width="600" 
            Height="410" Visibility="{Binding PDFVisible, Mode=TwoWay}" />

<FFmpegFramework:MediaElement Grid.Row="0" x:Name="MediaElement"
                 Height="400" Background="Gray"  Visibility="{Binding VideoVisible, Mode=TwoWay}" />